Method for producing silver halide photographic photosensitive emulsion

ABSTRACT

A silver halide photographic emulsion excellent in photographic characteristics, stability, etc. is prepared by using a copolymeric water soluble synthetic resin essentially consisting of a carboxylic acid group, an imidazole group and an acid amide group containing N(1,1-dimethyl-3-oxobutyl) aminocarbonyl group in place of gelatin.

United States Patent n91 Iguchi et al.

[451 Nov. 12, 1974 METHOD FOR PRODUCING SILVER I-IALIDE PHOTOGRAPI-IICPHOTOSENSITIVE EMULSION [75] Inventors: Shigeru Iguchi; Tetsuo Yano:

Tamotu Iwata, all of Kyoto, Japan [73] Assignee: Mitsubishi Paper Mills,Ltd., Tokyo,

Japan [22] Filed: Nov. 14, 1972 [21] Appl. No.: 306,382

[30] Foreign Application Priority Data Nov. 15, 1971 Japan 46-91337 [52]U.S. Cl. 96/114, 117/34 [51] Int. Cl G03c l/72 [58] Field of Search96/114, 87 R; 117/34 [56] References Cited UNITED STATES PATENTS3,165,412 l/l965 Minsk et al. 96/114 3,356,686 12/1967 Firestine et al.96/114 3,306,750 2/1967 Minsk et al. 96/114 3,241,969 3/1966 Hart et al96/114 OTHER PUBLICATIONS Photographische Korrespondenz, The Use ofSynthetic Plastics in Photo. Materials, Depauw, 1964, p. 21.

Synthetic Polymers for Photo. Silver Halide Emulsions," Mem. Fac.Industr. Arts, V. 18, p. 123, Yano, 1969.

Primary Examiner-David Klein Assistant ExaminerEdward C. KimlinAttorney, Agent, or Firm-Cushman, Darby & Cushman [57] ABSTRACT A silverhalide photographic emulsion excellent in photographic characteristics,stability. etc. is prepared by using a copolymeric water solublesynthetic resin essentially consisting of a carboxylic acid group, animidazole group and an acid amidegroup containingN(1,1-dimethyl-3-oxobutyl) aminocarbonyl group in place of gelatin.

3 Claims, N0 Drawings The present invention relates to a method forproducing a silver halide photographic lightsensitive emulsions using acopolymeri'c water soluble synthetic resin essentially consisting of acarboxylic acid group, imidazole group, and an acid amide groupcontaining N( l,l-dimethyl-3-oxobutyl) aminocarbonyl group. Thusobtained emulsions are excellent in photographic characteristics,stability, etc.

Silver halide photographic emulsions are usually prepared by reacting awater-soluble silver salt and a water-soluble halide in an aqueoussolution containing a colloid binder, usually gelatin. However, it isvery difficult to obtain gelatins which have constant physical andphotographic properties and most of these properties are deteriorated bybacterial decomposition during storage-or hydrolysis duringmanufacturing operation. Several methods have been proposed tosubstitute gelatin with water soluble synthetic polymers containingaminocarbonyl group, carboxylic acid group, an imidazole group in thesame molecule have the similar action on formation and growth ofcrystals or silver halide with that of gelatin. In this respect, seeBulletin of Japan Photographic Society (Vol. 29, page 22,- 1966). Thus,said water soluble synthetic resins can be used for production ofphotographic silver halide lightsensitive materials. With use of saidsynthetic resins it is possible to produce photographic silver halidelightsensitive materials of constant quality more easily than with theconventionally used gelatin which is a natural product. Moreover,isoelectric point, inhibition action for growth of silver halidecrystals, etc. can be freely adjusted by suitable choice of theproportion of carboxylic acid group and imidazole group.

However, the restrainingproperties of said synthetic resins for thegrowth of crystals varies depending upon whether the silver halide issilver chloride or bromide. That is, the synthetic resins which have thesame restraining action for growth of crystals of silver chloride as theusual gelatinhave smaller restraining action for growth of crystals ofsilver bromide. Therefore, when gelatin is substituted with suchsynthetic resins which yield the same particles of silver chlorideemulsion as gelatin does, coarse particles of silver bromide emulsionare obtained. Increase of the content of imidazole group in saidsynthetic resins causes the same result for silver bromide emulsion asgelatin, but the restraining action for silver chloride emulsion becomestoo strong and the particles become fine to lower the sensitivity.

The inventors have found that said synthetic resins into which the N(l,l-dimethyl-3-oxobutyl) aminocarbonyl group is introduced can increaserestraining power for growth of silver bromide crystals and with use ofsaid resins the restraining action for growth of silver chloridecrystals and silver bromide crystals can freely be adjusted. I

That is, according to the present invention, the restraining action forgrowth of crystals of silver chloride and silver bromide can be made thesame as that of gelatin and furthermore it also becomes possible toattain restraining actions of desired degree for silver chloride andsilver bromide, respectively.

Introduction of N(l,l-dimethyl-3-oxobutyl) aminocarbonyl group into thesynthetic resins can be carried 2 out by adding acyl N(l,l-dimethyl-3-oxobutyl) amide CH: (0H,:CH-CO-NH- 43-01-1 C0-C3;Diacetone acrylamide):

monomers prior to polymerization and then conducting polymerizationin'accordance with the usual method.

The hydrophilic monomers used for copolymerv ization with diacetoneacylamide in the present inven tion are acid amide such as acrylamide ormethacrylamide; carboxylic acid such as acrylic acid or methacrylicacid; and vinylimidazole derivatives having the general formula (whereinone of R, R', R" and R' is vinyl group and the other are hydrogen, alkylor hydroxyalkyl). For example, l-vinyl-imidazole, 5-vinyl-imidazole,l-vinyl-2- methylimidazole, l-vinyl-2-e thyl-imidazole, l-vinyl-2,4-dimethyl-limidazole, l -vinyl-2-ethyl-4-methylimida'zole,l-vinyl-4(or 5) B-hydroxyethyl-imidazole, l-vinyl-2-Bhydroxyethyl-imidazole, etc. may be used.

The essential structure of the water soluble synthetic resin in thepresent invention is as follows:

M (some) or more) My (20 mol or less) The proportion of each monomer inthe synthetic resin necessary for providing standard speed of growth ofsilver halide particles, is suitably vinylimidazle derivative 8 molcarboxylic acid such as acrylic acid or methacrylic acid 7 mol acidamide such as acrylamide or methacrylamide 65 mol and diacetoneacrylamide 20 mo] However, when synthetic resins capable of stronglyinhibiting the growth of silverchloride ide, the selective restrainingeffect for growth of silver bromide particles is unchanged. Moreover,even if the kind of imidazole derivative varies, no difference is causedin the effect The amount of diacetone acrylamide in the synthetic resincan freely be chosen in an extremely wide range. However, for thepurpose of the present invention, less than 1 mol of diacetoneacrylamide can attain substantially no effect. On the other hand, whenthe amount is more thanabout 50 mol the resin becomes insoluble in waterand cannot be used for production of silver halide emulsion. The contentof the vinylimidazole derivative is practically mol or less and when thecontent exceeds 20 mol the growth of silver halide particles isextremely inhibited and when less than .1 sufficient effect cannot beobtained. The content of carboxylic acid is preferably mol or less andmore than about 0.2 mol is prefered and the balance is the acid amide.The isoelectric point of the resin is mainly determined by the ratio ofthe carboxylic acid to vinylimidazole and when the ratio varies between02 and 5, the isoelectric point changes from 8 to 4. The contents ofthese components may be increased or decreased depending upon thedesired speed of growth of silver halide particles and isoelectricpoint.

The synthetic resins used in the present invention have markedlyexcellent properties in the production of emulsion as mentioned above.Aqueous solution of the resin does not have the ability to gel oncooling and hence it cannot be applied in the same manner as gelatin.Gelatin and the like materials having gelling ability are added to theemulsion and then the emulsion is applied in a thin layer to a supportsuch as paper, film, etc., and thereafter the fluidity of the emulsionis lost by cooling or other means, or the emulsion viscosity of which isincreased is applied by air knife or other means and then is rapidlycooled. Thus obtained lightsensitive material can be developed and fixedin the same manner as the usual silver halide lightsensitive materials.However, the speed of development-fixation is rapid and the developmenttime can be shortened to several tenths that of the usual lightsensitivematerial. This is an important advantage especially in color developmentor rapid developing.

The synthetic resins used in the present invention may be added in theform of an aqueous solution during emulsification and/or ripening. Theamount of the synthetic resins added may be less than that of gelatinwhich may be about 1/6 7 times that of silver halide.

The watersoluble synthetic resins used in the present invention may beprepared in the following manner. Preparation Example 1 The followingtwo liquids were firstly prepared.

Nitric acid was added to the above liquid to adjust pH to 6 6.5.

Liquid 2 Potassium persulfate To the liquid 2 into which nitrogen gashadbeen sufficiently allowed to pass and which was then kept at C wasdropped the liquid 1 over a period of minutes while stirring. Aftercompletion of the addition, the liquid was maintained at 70C for afurther 30 minutes to complete polymerization and thereafter, 4 ml of 3methanol solution of dihydroxyethylaniline was added to conduct atreatment at 70C for 30 minutes to decompose the residual potassiumpersulfate. Thus obtained aqueous solution of synthetic resin may beused or stored in the form of aqueous solution. When it is necessary touse the resin in a solid form, the resin solution is subjected toprecipitation-purification with methanol in an amount about 10 times theamount of the resin solution to recover as a solid.

The compositions of thus obtained synthetic resin were amide group 60mol diacetoneacrylamide group 25 mol imidazole 9 mol and carboxylic acidgroup 6 mol Preparation Example 2 ln place of carrying out thecopolymerization of the four monomers, copolymerization of the followingthree monomers with omission of acrylic acid was effected and thereaftera part of amide group'was hydrolyzed to convert it into carboxylic acidgroup to obtain a similar synthetic resin.

MO wlll NQNN WUQENUQUQUQ Liquid 2 Potassium persulfate 0.54 Water I 74(NOW Sufficient nitrogen gas was passed through the liquid 2 and then tosaid liquid kept at 70C was dropped the liquid 1 over a period of 90minutes. Thereafter, the liquid was further kept at 70C for 30 minutes.

Thereafter, 4 ml. of 3 solution of N-dihydroxyethyl aniline was added tosaid liquid and then the liquid was kept at 70C for further 30 minutes.Thus obtained synthetic resin solution can be used for production ofemulsion, but the resin is hydrolyzed to introduce carboxylic acid groupto adjust the isoelectric point and the speed of growth of silver halideparticles. For this purpose, 45 ml of 10 sodium hydroxide solution wasadded to said resin solution and the solution was heated at 70C for 30minutes. Thereafter, 10 ml. of 70 nitric acid was added thereto and thesolution was neutralized and then cooled. If necessary, as inPreparation Example I, the synthetic resin solution can be added tomethanol in an amount about 5 times that of the resin solution toprecipitate and recover the resin.

About 8 mol of the side chain of thus obtained polymer was imidazolegroup, about 7 mol was carboxylic acid group, about 20 mol wasdiacetoneaover a period of one minute. Thereafter, digestion was carriedout at 60C for 35 minutes and then the liquid was cooled to 40C and 450g of 40 aqueous solution of sodium sulfate was added to precipitateemulsion.

growth of crystals P Silver halide standard g 5 The precipitate removedfrom mother liquor by centriftm and can be utilized for production ofphotograph1c ugalization was added to 100 ml of water and dissolvedemulsions. The growth of crystals can be intensively reat 60C.Thereafter, to the resultant solution was added strained by increasingthe content of vinylimidazole to 5 ml of potassium iodide solution and 5ml of 0.0] obtain synthetic resin suitable for production of fine sodiumthiosulfate solution and digestion was carried grain emulsion. On theother hand, when the content out for minutes to obtain a contrastemulsion having of vinylimidazole is decreased, growth of grains bethesimilar sensitivity to that of chlorobromide printing comes easy.emulsion used for enlargement.

Example 3 Synthetic resin of Preparation Example 2 20 g Liquid A Water600 g (40C) Ammonium bromide 63.5 g Potassium iodide 2 g Silver nitrate100 g Liquid B ammonia water about 80 ml (27C) 7 (total amount) Waterwas added to obtain 300 ml of liquid Emulsions were prepared using thesynthetic resins of 5 Liquid B was added to liquid A while stirring overa Preparation Examples 1 and 2 as shown in the followperiod of 30seconds and digestion was carried out at ing- Examples. N 40C f9r4minutes. The temperature of thus obtained Example 1 Synthetic resin ofPreparation Example 1 4 3 Li uid A Water 150 g (5 .Qitris 29kt... I s 6Nsodium hydroxide solution 1 3 Silver nitrate l0 3 Liquid B Distilledwater 50 g (50C) Lead nitrate (S aqueous solution) 2 g Sodium chloride4.5 g Liquid C {Cadmium chloride 2.5 g (38C) Water 50 g Liquid B wasadded to liquid A while stirring within emulsion was rapidly decreasedto room temperature one minute and furthermore liquid C was added andsulfuric acid was added thereto to ad ust pH to 4. thereto. Thereafter,they were digested at 50C for 35 To the resultant emulsion was added1500 g of 40 minutes and 5 g of l potassium iodide solution wasmagnesium sulfate to precipitate silver halide and resin added anddigestion was continued for 20 minutes to and the useless halogen saltand ammonium salt were obtain an emulsion for printing paper suitablefor removed. 600 g of water was added to the precipitate contactprinting. I and heated to 55C to dissolve the precipitate. To the Nearlythe same emulsion was obtained using the resultant emulsion were added50 g of 0.02 sodium synthetic resin of Preparation Example 2 in place ofthe thiosulfate solution and 100 g of 0.02 aqueous solusynthetic resinof Preparation Example l. tion of ade nine and digestion was carried outat C Example 2 Synthetic resin of Preparation Example 2 4 5 Liquid AWater 150 g (C) Citric acid l g 6N sodium hydroxide l 3 Silver nitrate10 g Li uid B Distilled water 50 g (6 C) Lead nitrate (5 aqueoussolution) 2 g Sodium chloride 4.5 g Potassium bromide 3.5 3 Liquid CCadmium chloride (50C) (l0 aqueous solution) 10 3 Water 50 g Liquid B a.kidritaiiflid A while stirring within 1 minute and furthermoreliquid Cwas added thereto for minutes to obtain silver iodobromide emulsion ofishssnsi vit s 0500 (NGQ W (mourn Liquid B and liquid C were added toliquid A while vigorously stirring over a period of 30 seconds.Thereafter, liquid D and liquid E were added thereto over a period of 50minutes.

Precipitation and other treatments were carried out inthe same manner asin Example 2 to obtain fine grain and contrast emulsion.

The above emulsions obtained had constant properties and hadphotographic characteristics which are of less deviation than whengelatin was used. Moreover, change of the emulsion with lapse of timewas less than that of gelatin emulsions and they were stable. Therefore,they can be stored for a long period of time and furthermore they can beleft in a state of solution for a long time.

What is claimed is:

1. In a method for preparing photographic light sensitive silver halideemulsions, the improvement in said method of using in place of gelatin awater soluble synthetic resin of the structure consisting essentially ofW l a V rnol or more where:

R is H or methyl; R is H or methyl where one of R, R, R" and R' isreplacedby the bond attached to the group and the remainder of R, R, R"and R are hydrogen, alkyl or hydroxylalkyl.

2. A photographic lightsensitive silver halide emul- I during at leastone of emulsification and ripening.

1. IN A METHOD FOR PREPARING PHOTOGRAPHIC LIGHT SENSITIVE SILVER HALIDEEMULSIONS, THE IMPROVEMENT IN SAID METHOD OF USING IN PLACE OF GELATIN AWATER SOLUBLE SYNTHETIC RESIN OF THE STRUCTURE CONSISTING ESSENTIALLY OF2. A photographic light-sensitive silver halide emulsion containing thewater soluble copolymeric synthetic resin as defined in claim
 1. 3. Amethod according to claim 1, wherein the synthetic resin is added in theform of an aqueous solution during at least one of emulsification andripening.